Abstract.

Objective and design:

Genetics may influence wear particle-induced inflammatory osteolysis after joint replacement. In the present work, mice with three different genetic backgrounds were used to test this hypothesis.

Treatment:

C57BL/6J, Balb/c and Kunming mouse were used. Each kind of mouse was divided into those receiving 30 mg UHMWPE particle implantation onto the calvariae and those receiving a sham operation.

Methods:

Mice of each group were sacrificed one week after surgery. Calvariae were harvested for immunological assay of TNF-α and IL-1β secretion in supernatants of calvariae organ culture and histological analysis of calvarial sagittal suture osteolysis and osteoclastogenesis.

Results:

Although UHMWPE particles induced obvious calvarial sagittal suture osteolysis and osteoclastogenesis in all strains as compared with their corresponding control mice, the most significant change was found in C57BL/6J mice, less severe in Balb/c mice and much less severe in Kunming mice. In agreement with pathological findings, UHMWPE particles induced the highest IL-1β secretion in C57BL/6J mice, compared with Balb/c and Kunming mice. However, no difference was observed concerning TNF-α secretion among these mice.

Conclusion:

Our data suggests that genetics had a significant influence on wear particle-induced inflammation, osteoclastogenesis and osteolysis. The influence of genetic background on implant life in patients with joint replacement warrants further investigation.

Keywords:

Wear particles Osteolysis Mouse genetics

Received 6 March 2007; returned for revision 18 April 2007; returned for final revision 2 October 2007; accepted by M. Parnham 7 October 2007